V3: Get rid of separate interrupt pool. This is well handled
by irq_get_descs and irq_free_descs. Two functions I simply
wasn't aware of previously. Thus the allocation for a given
trigger is now handled by core code rather than us reinventing
the wheel.
V2: Stop silly name duplication.
Move pool handling to industrialio-trigger as that is the only user.
Changed over to using irq_modify_status rather than the arm
specific set_irq_flags as per Thomas Gleixner's suggestion.
Signed-off-by: Jonathan Cameron <jic23@xxxxxxxxx>
---
drivers/staging/iio/Kconfig | 7 +
drivers/staging/iio/industrialio-trigger.c | 175 +++++++++++++++++++++++-----
drivers/staging/iio/trigger.h | 57 ++++++++-
3 files changed, 203 insertions(+), 36 deletions(-)
diff --git a/drivers/staging/iio/Kconfig b/drivers/staging/iio/Kconfig
index 6775bf9..e6235d1 100644
--- a/drivers/staging/iio/Kconfig
+++ b/drivers/staging/iio/Kconfig
@@ -48,6 +48,13 @@ config IIO_TRIGGER
ring buffers. The triggers are effectively a 'capture
data now' interrupt.
+config IIO_CONSUMERS_PER_TRIGGER
+ int "Maximum number of consumers per trigger"
+ depends on IIO_TRIGGER
+ default "2"
+ help
+ This value controls the maximum number of consumers that a
+ given trigger may handle. Default is 2.
source "drivers/staging/iio/accel/Kconfig"
source "drivers/staging/iio/adc/Kconfig"
diff --git a/drivers/staging/iio/industrialio-trigger.c b/drivers/staging/iio/industrialio-trigger.c
index 083847c..5496ee2 100644
--- a/drivers/staging/iio/industrialio-trigger.c
+++ b/drivers/staging/iio/industrialio-trigger.c
@@ -163,6 +163,7 @@ static struct iio_trigger *iio_trigger_find_by_name(const char *name,
void iio_trigger_poll(struct iio_trigger *trig, s64 time)
{
+ int i;
struct iio_poll_func *pf_cursor;
list_for_each_entry(pf_cursor, &trig->pollfunc_list, list) {
@@ -178,6 +179,13 @@ void iio_trigger_poll(struct iio_trigger *trig, s64 time)
trig->use_count++;
}
}
+ if (!trig->use_count) {
+ for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++)
+ if (trig->subirqs[i].enabled) {
+ trig->use_count++;
+ generic_handle_irq(trig->subirq_base + i);
+ }
+ }
}
EXPORT_SYMBOL(iio_trigger_poll);
@@ -219,16 +227,31 @@ int iio_trigger_attach_poll_func(struct iio_trigger *trig,
int ret = 0;
unsigned long flags;
- spin_lock_irqsave(&trig->pollfunc_list_lock, flags);
- list_add_tail(&pf->list, &trig->pollfunc_list);
- spin_unlock_irqrestore(&trig->pollfunc_list_lock, flags);
-
- if (trig->set_trigger_state)
- ret = trig->set_trigger_state(trig, true);
- if (ret) {
- printk(KERN_ERR "set trigger state failed\n");
- list_del(&pf->list);
+ if (pf->thread) {
+ bool notinuse
+ = bitmap_empty(trig->pool,
+ CONFIG_IIO_CONSUMERS_PER_TRIGGER);
+
+ pf->irq = iio_trigger_get_irq(trig);
+ ret = request_threaded_irq(pf->irq, pf->h, pf->thread,
+ pf->type, pf->name,
+ pf);
+ if (trig->set_trigger_state && notinuse) {
+ ret = trig->set_trigger_state(trig, true);
+ } else {
+ spin_lock_irqsave(&trig->pollfunc_list_lock, flags);
+ list_add_tail(&pf->list, &trig->pollfunc_list);
+ spin_unlock_irqrestore(&trig->pollfunc_list_lock, flags);
+
+ if (trig->set_trigger_state)
+ ret = trig->set_trigger_state(trig, true);
+ }
+ if (ret) {
+ printk(KERN_ERR "set trigger state failed\n");
+ list_del(&pf->list);
+ }
}
+
return ret;
}
EXPORT_SYMBOL(iio_trigger_attach_poll_func);
@@ -240,37 +263,63 @@ int iio_trigger_dettach_poll_func(struct iio_trigger *trig,
unsigned long flags;
int ret = -EINVAL;
- spin_lock_irqsave(&trig->pollfunc_list_lock, flags);
- list_for_each_entry(pf_cursor, &trig->pollfunc_list, list)
- if (pf_cursor == pf) {
- ret = 0;
- break;
- }
- if (!ret) {
- if (list_is_singular(&trig->pollfunc_list)
- && trig->set_trigger_state) {
- spin_unlock_irqrestore(&trig->pollfunc_list_lock,
- flags);
- /* May sleep hence cannot hold the spin lock */
+ if (pf->thread) {
+ bool no_other_users
+ = (bitmap_weight(trig->pool,
+ CONFIG_IIO_CONSUMERS_PER_TRIGGER)
+ == 1);
+ if (trig->set_trigger_state && no_other_users) {
ret = trig->set_trigger_state(trig, false);
if (ret)
goto error_ret;
- spin_lock_irqsave(&trig->pollfunc_list_lock, flags);
+ } else
+ ret = 0;
+ iio_trigger_put_irq(trig, pf->irq);
+ free_irq(pf->irq, pf);
+ } else {
+ spin_lock_irqsave(&trig->pollfunc_list_lock, flags);
+ list_for_each_entry(pf_cursor, &trig->pollfunc_list, list)
+ if (pf_cursor == pf) {
+ ret = 0;
+ break;
+ }
+ if (!ret) {
+ if (list_is_singular(&trig->pollfunc_list)
+ && trig->set_trigger_state) {
+ spin_unlock_irqrestore(&trig
+ ->pollfunc_list_lock,
+ flags);
+ /* May sleep hence cannot hold the spin lock */
+ ret = trig->set_trigger_state(trig, false);
+ if (ret)
+ goto error_ret;
+ spin_lock_irqsave(&trig->pollfunc_list_lock,
+ flags);
+ }
+ /*
+ * Now we can delete safe in the knowledge that, if
+ * this is the last pollfunc then we have disabled
+ * the trigger anyway and so nothing should be able
+ * to call the pollfunc.
+ */
+ list_del(&pf_cursor->list);
}
- /*
- * Now we can delete safe in the knowledge that, if this is
- * the last pollfunc then we have disabled the trigger anyway
- * and so nothing should be able to call the pollfunc.
- */
- list_del(&pf_cursor->list);
+ spin_unlock_irqrestore(&trig->pollfunc_list_lock, flags);
}
- spin_unlock_irqrestore(&trig->pollfunc_list_lock, flags);
error_ret:
return ret;
}
EXPORT_SYMBOL(iio_trigger_dettach_poll_func);
+irqreturn_t iio_pollfunc_store_time(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ pf->timestamp = iio_get_time_ns();
+ return IRQ_WAKE_THREAD;
+}
+EXPORT_SYMBOL(iio_pollfunc_store_time);
+
/**
* iio_trigger_read_currrent() - trigger consumer sysfs query which trigger
*
@@ -337,6 +386,22 @@ static const struct attribute_group iio_trigger_consumer_attr_group = {
static void iio_trig_release(struct device *device)
{
struct iio_trigger *trig = to_iio_trigger(device);
+ int i;
+
+ if (trig->subirq_base) {
+ for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++) {
+ irq_modify_status(trig->subirq_base + i,
+ IRQ_NOAUTOEN,
+ IRQ_NOREQUEST | IRQ_NOPROBE);
+ irq_set_chip(trig->subirq_base + i,
+ NULL);
+ irq_set_handler(trig->subirq_base + i,
+ NULL);
+ }
+
+ irq_free_descs(trig->subirq_base,
+ CONFIG_IIO_CONSUMERS_PER_TRIGGER);
+ }
kfree(trig);
iio_put();
}
@@ -345,11 +410,30 @@ static struct device_type iio_trig_type = {
.release = iio_trig_release,
};
-struct iio_trigger *iio_allocate_trigger(void)
+static void iio_trig_subirqmask(struct irq_data *d)
+{
+ struct irq_chip *chip = irq_data_get_irq_chip(d);
+ struct iio_trigger *trig
+ = container_of(chip,
+ struct iio_trigger, subirq_chip);
+ trig->subirqs[d->irq - trig->subirq_base].enabled = false;
+}
+
+static void iio_trig_subirqunmask(struct irq_data *d)
+{
+ struct irq_chip *chip = irq_data_get_irq_chip(d);
+ struct iio_trigger *trig
+ = container_of(chip,
+ struct iio_trigger, subirq_chip);
+ trig->subirqs[d->irq - trig->subirq_base].enabled = true;
+}
+
+struct iio_trigger *iio_allocate_trigger_named(const char *name)
{
struct iio_trigger *trig;
trig = kzalloc(sizeof *trig, GFP_KERNEL);
if (trig) {
+ int i;
trig->dev.type = &iio_trig_type;
trig->dev.bus = &iio_bus_type;
device_initialize(&trig->dev);
@@ -357,10 +441,41 @@ struct iio_trigger *iio_allocate_trigger(void)
spin_lock_init(&trig->pollfunc_list_lock);
INIT_LIST_HEAD(&trig->list);
INIT_LIST_HEAD(&trig->pollfunc_list);
+
+ if (name) {
+ mutex_init(&trig->pool_lock);
+ trig->subirq_base
+ = irq_alloc_descs(-1, 0,
+ CONFIG_IIO_CONSUMERS_PER_TRIGGER,
+ 0);
+ if (trig->subirq_base < 0) {
+ kfree(trig);
+ return NULL;
+ }
+ trig->name = name;
+ trig->subirq_chip.name = name;
+ trig->subirq_chip.irq_mask = &iio_trig_subirqmask;
+ trig->subirq_chip.irq_unmask = &iio_trig_subirqunmask;
+ for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++) {
+ irq_set_chip(trig->subirq_base + i,
+ &trig->subirq_chip);
+ irq_set_handler(trig->subirq_base + i,
+ &handle_simple_irq);
+ irq_modify_status(trig->subirq_base + i,
+ IRQ_NOREQUEST | IRQ_NOAUTOEN,
+ IRQ_NOPROBE);
+ }
+ }
iio_get();
}
return trig;
}
+EXPORT_SYMBOL(iio_allocate_trigger_named);
+
+struct iio_trigger *iio_allocate_trigger(void)
+{
+ return iio_allocate_trigger_named(NULL);
+}
EXPORT_SYMBOL(iio_allocate_trigger);
void iio_free_trigger(struct iio_trigger *trig)
diff --git a/drivers/staging/iio/trigger.h b/drivers/staging/iio/trigger.h
index c6ab32f..0c44c5e 100644
--- a/drivers/staging/iio/trigger.h
+++ b/drivers/staging/iio/trigger.h
@@ -6,9 +6,15 @@
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*/
+#include <linux/irq.h>
+
#ifndef _IIO_TRIGGER_H_
#define _IIO_TRIGGER_H_
+struct iio_subirq {
+ bool enabled;
+};
+
/**
* struct iio_trigger - industrial I/O trigger device
*
@@ -43,6 +49,13 @@ struct iio_trigger {
int (*set_trigger_state)(struct iio_trigger *trig, bool state);
int (*try_reenable)(struct iio_trigger *trig);
+
+ struct irq_chip subirq_chip;
+ int subirq_base;
+
+ struct iio_subirq subirqs[CONFIG_IIO_CONSUMERS_PER_TRIGGER];
+ unsigned long pool[BITS_TO_LONGS(CONFIG_IIO_CONSUMERS_PER_TRIGGER)];
+ struct mutex pool_lock;
};
static inline struct iio_trigger *to_iio_trigger(struct device *d)
@@ -114,6 +127,27 @@ int iio_trigger_dettach_poll_func(struct iio_trigger *trig,
void iio_trigger_poll(struct iio_trigger *trig, s64 time);
void iio_trigger_notify_done(struct iio_trigger *trig);
+static inline int iio_trigger_get_irq(struct iio_trigger *trig)
+{
+ int ret;
+ mutex_lock(&trig->pool_lock);
+ ret = bitmap_find_free_region(trig->pool,
+ CONFIG_IIO_CONSUMERS_PER_TRIGGER,
+ ilog2(1));
+ mutex_unlock(&trig->pool_lock);
+ if (ret >= 0)
+ ret += trig->subirq_base;
+
+ return ret;
+};
+
+static inline void iio_trigger_put_irq(struct iio_trigger *trig, int irq)
+{
+ mutex_lock(&trig->pool_lock);
+ clear_bit(irq - trig->subirq_base, trig->pool);
+ mutex_unlock(&trig->pool_lock);
+};
+
/**
* struct iio_poll_func - poll function pair
*
@@ -125,11 +159,14 @@ void iio_trigger_notify_done(struct iio_trigger *trig);
* @poll_func_main: function in here is run after all immediates.
* Reading from sensor etc typically involves
* scheduling from here.
- *
- * The two stage approach used here is only important when multiple sensors are
- * being triggered by a single trigger. This really comes into its own with
- * simultaneous sampling devices where a simple latch command can be used to
- * make the device store the values on all inputs.
+ * @h: the function that is actually run on trigger
+ * @thread: threaded interrupt part
+ * @type: the type of interrupt (basically if oneshot)
+ * @irq: the corresponding irq as allocated from the
+ * trigger pool
+ * @timestamp: some devices need a timestamp grabbed as soon
+ * as possible after the trigger - hence handler
+ * passes it via here.
**/
struct iio_poll_func {
struct list_head list;
@@ -137,12 +174,20 @@ struct iio_poll_func {
void (*poll_func_immediate)(struct iio_dev *indio_dev);
void (*poll_func_main)(struct iio_dev *private_data, s64 time);
+ irqreturn_t (*h)(int irq, void *p);
+ irqreturn_t (*thread)(int irq, void *p);
+ int type;
+ char *name;
+ int irq;
+ s64 timestamp;
};
int iio_alloc_pollfunc(struct iio_dev *indio_dev,
void (*immediate)(struct iio_dev *indio_dev),
void (*main)(struct iio_dev *private_data, s64 time));
+irqreturn_t iio_pollfunc_store_time(int irq, void *p);
+
/*
* Two functions for common case where all that happens is a pollfunc
* is attached and detached from a trigger
@@ -151,7 +196,7 @@ int iio_triggered_ring_postenable(struct iio_dev *indio_dev);
int iio_triggered_ring_predisable(struct iio_dev *indio_dev);
struct iio_trigger *iio_allocate_trigger(void);
-
+struct iio_trigger *iio_allocate_trigger_named(const char *name);
void iio_free_trigger(struct iio_trigger *trig);
#endif /* _IIO_TRIGGER_H_ */
--
1.7.3.4
--
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